Urbanization expands the fluctuating difference in gross primary productivity between urban and rural areas from 2000 to 2018 in China

Xiaoyan Liu; Yaoping Cui; Wanlong Li; Mengdi Li; Nan Li; Zhifang Shi; Jinwei Dong; Xiangming Xiao

doi:10.1016/j.scitotenv.2023.166490

Urbanization expands the fluctuating difference in gross primary productivity between urban and rural areas from 2000 to 2018 in China

Sci Total Environ. 2023 Nov 25:901:166490. doi: 10.1016/j.scitotenv.2023.166490. Epub 2023 Aug 21.

Authors

Xiaoyan Liu¹, Yaoping Cui², Wanlong Li³, Mengdi Li³, Nan Li³, Zhifang Shi³, Jinwei Dong⁴, Xiangming Xiao⁵

Affiliations

¹ Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions (Henan University), Ministry of Education, Kaifeng 475001, Henan, China; School of Geography and Environmental Science, Henan University, Kaifeng 475004, China; Dabieshan National Observation and Research Field Station of Forest Ecosystem at Henan, Zhengzhou 450046, China; Xinyang Ecological Research Institute, Xinyang 464000, China.
² Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions (Henan University), Ministry of Education, Kaifeng 475001, Henan, China; School of Geography and Environmental Science, Henan University, Kaifeng 475004, China; Dabieshan National Observation and Research Field Station of Forest Ecosystem at Henan, Zhengzhou 450046, China; Xinyang Ecological Research Institute, Xinyang 464000, China. Electronic address: cuiyp@lreis.ac.cn.
³ Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions (Henan University), Ministry of Education, Kaifeng 475001, Henan, China; School of Geography and Environmental Science, Henan University, Kaifeng 475004, China.
⁴ Institute of Geographical Sciences and Resources, Chinese Academy of Sciences, Beijing 100101, China.
⁵ Department of Microbiology and Plant Biology, Center for Earth Observation and Modeling, University of Oklahoma, Norman, OK 73019, USA. Electronic address: xiangming.xiao@ou.edu.

PMID: 37611713
DOI: 10.1016/j.scitotenv.2023.166490

Abstract

Urban and rural vegetation are affected by both climate change and human activities, but the role of urbanization in vegetation productivity is unclear given the dual impacts. Here, we delineated urban area (UA) and rural area (RA), quantified the relative impacts of climate change and human activities on gross primary production (GPP) in 34 major cities (MCs) in China from 2000 to 2018, and analyzed the intrinsic impacts of urbanization on GPP. First, we found that the total urban impervious surface coverage (ISC) of the 34 MCs increased by 13.25 % and the mean annual GPP increased by 211 gC m^-2 during the study period. GPP increased significantly in urban core areas, but decreased significantly in urban expansion areas, which was mainly due to a large amount of vegetation loss due to land use conversion. Second, the variability of GPP in UA was generally lower than in RA. Both climate change and human activities had a positive impact on GPP in UA and RA in the 34 MCs, of which the contribution was 49 % and 51 % in UA, and 76 % and 24 % in RA, respectively. Third, under climate change and human activities, the increase in GPP offset 4.96 % and 12.35 % of the impact of land use conversion on GPP in 2000 and 2018, respectively, which indicated that the offset strengthened over time. These findings emphasize the role of human activities in promoting carbon sequestration in urban vegetation, which is crucial for better understanding the processes and mechanisms of urban carbon cycles. Decision-makers can manage urban vegetation based on vegetation carbon sequestration potential as regions urbanize, aiding comprehensive decision-making.

Keywords: Climate change; Gross primary productivity; Growth offset; Human activity; Urbanization.